High-speed symmetrical opening photographic shutter



FUERST 2,448,876

HIGH SPEEi) SYMMETRICAL OPENING -PHOTOGRAPHIC SHUTTER Filed May 21, 1945 8 Sheets-Sheet l CARL C. FUERST INVENTOR ATTORNEYS Sept. 7, 1948. c, g, FUERST 2,448,876 HIGH SPEED SYMMETRICAL OPENING PHOTOGRAPHIC SHUTTER Filed Bay 21, 1945 r '8 Sheets-Sheet 2 v 2g lZ//////////7///// //X CARL c. FUERST INVEIYTQR WW A TTORNE YS Sept. 7, 1948. c. c. FUERST HIGH SPEED SYMMETRICAL OPENING PHOTOGRAPHIC SHUTTER 8 Sheets-Sheet 3 Filed May 21, 1945 C RL-,0 'FUERST INVENTOR I ATTORNEYS p 1948- c. c. FUERST 2,448,876

HIGH SPEED SYMMETRICAL OPENING PHOTOGRAPHIC SHUTTER Filed May 21, 1945 a s eds-sheep 4 valuing/W7 /l/lz/ gCjAR 1-...c. FUERST INVENIOR A'ITORNEiS Sept. 7, 1948. c. c. FUERST 2,448,876

HIGH SPEED SYMMETRICAL OPENING PHOTOGRAPHIC SHUTTER Filed May 21, 1945 8 Sheets-Sheet 5 ARL c. FUERST INVENTOR 90 A TTORNE YS Sept. 7, 1948. c, c, FUERST 2,448,876

HIGH SPEED SYMMETRICAL OPENING PHOTOGRAPHIC SHUTTER Filed May 21, 1945 8 Sheets-Sheet 6 CARL C.FUERST INVENTOR WW BY A TTORNEYS Sept. 7, 1948. c. c. FUERST 2,448,876

HIGH SPEED SYMMETRICAL OPENING PHOTOGRAPHIG SHUTTER Filed May 21, 1945 8 Sheets-Sheet 8 J84 CARL c. FUERST INVENTOR ATTORNEYS Patented Sept. 7, 1948 HIGH-SPEED SYIVIBEETRICAL OPENING PHOTOGRAPHIC SHUTTER Carl C. Fuerst, Rochester, N. Y., assignor to Eastman Kodak Company, Rochester, N. Y., a corporation of New Jersey Application May 21, 1945, Serial No. 595,033

49 Claims. 1

This invention relates to photography and particularly to an improved form of between-thelens shutter. One object of my invention is to provide a shutter mechanism which is capable of obtaining extremely short exposures. Another object of my invention is to provide a shutter of the so-called setting type with a single operating lever which serves both to set the shutter for an exposure when moved in one direction and for a trigger for releasing the shutter mechanism when said operating member is moved in a reverse direction. Another object of my invention is to provide a shutter with a setting and releasing mechanism so arranged that the setting mech anism does not impede the operation of the shutter during an exposure. Another object of my invention is to provide a shutter with a shutter releasing mechanism so arranged that the actual release of the shutter mechanism is accomplished automatically after the manual operation of the releasing lever. A still further object of my invention is to provide a shutter with a power driven releasing mechanism and a manual control therefor arranged so that extremely light pressure on the control member will release the power-operated member which in turn releases the shutter mechanism. A still further object of my invention is to provide a power-operated releasing mechanism and to provide a means for controlling its time of operation. A further object of my invention is to provide a means for accurately predetermining the synchronism of a flash lamp with the operation of the shutter leaves and for varying this timing to suit the characteristics of different flash lamps. A still further object of my invention is to provide an improved shutter mechanism in which the inertia of the operating parts is reduced to a minimum and in which the actual moving parts for making an exposure are also reduced to a minimum whereby high-speed exposures may be obtained. A still further object of my invention is to provide a means for varying the effect of the master member and for altering the driving relationship between the master member and the shutter blade operating ring.

. Other objects will appear from the following specification, the novel features being particularly pointed out in the claims at the end thereof.

This application is a continuation-in-part of my copending application Serial No. 549,529, Photographic shutter, filed August 15, 1944, now abandoned.

In the drawings wherein like reference characters denote like parts throughout:

Fig. 1 is a front elevation of a typical shutter constructed in accordance with, and embodying, a preferred form of my invention;

Fig. 2 is a. front elevation of a preferred form of shutter blades and shutter blade operating rings used in the shutter of Fig. 1. This view shows only certain parts in a set position ready for an exposure;

Fig. 3 is a view similar to Fig. 2 but with the parts moved to their released position which they assume 'after an exposure has been made;

Fig. 4 is an enlarged front elevation of the shutter shown in Fig. 1, but with the shutter cover and adjusting cams removed to expose the mechanism;

Fig. 5 is a fragmentary detail section through the master member and associated parts taken on line 5-5 of Fig. 4;

Fig. 6 is a fragmentary detail front elevation of parts of the shutter actuating mechanism, parts being omitted for clearness;

Fig. 7 is a fragmentary detail front elevation of certain shutter parts including the blade operating rings and certain controls therefor;

Fig. 8 is an enlarged schematic fragmentary sectional view through a portion of the shutter shown in Fig. 1, a portion of this view (shown by section line AA) being taken through a portion of the blade ring arm to show the relation of these parts in the shutter casing chambers;

Fig. 9 is an enlarged fragmentary front plan view of a portion of the blade rings and master member, the parts being shown in a set position and for exposures of normal automatic speeds;

Fig. 10 is a view similar to Fig. 9 but with the parts positioned for a high speed exposure. The parts are in a set position;

Fig. 11 is a view substantially similar to Figs. 8 and 9 but with the parts in position to open the blades as the master member moves from one contact surface to another;

Fig. 12 is a view similar to the views of Figs. 9 to 11, inclusive, but with the parts in their exposed or fully closed position;

Fig. 13 is a fragmentary detail showing the blade ring latch in an operative position;

Fig. 14 is an enlarged fragmentary front view showing the shutter setting and releasing mechanism, the parts being shown in a fully set position for an exposure of /2 of a second;

Fig. 15 is a view similar to Fig. 14 but with the parts shown released for a bulb exposure, the blades being fully open;

Fig. 16 is a fragmentary detail plan of the operating handle latch;

Fig. 17 is a view similar to Figs. 14 and .15, but with the parts set for extreme high speed;

Fig. 18 is a detail plan view showing portions of the high speed mechanism with auxiliary spring tensioned;

Fig. 19 is a section taken on line I9-l9 of Fig. 1'7;

Fig. 20 is a front view with parts removed showing diaphragm leaves and operating mechanism;

Fig. 21 is an enlarged section taken on line 2 l 2! of Fig. 20;

Fig. 22 shows the speed adjusting cam removed from the shutter, the cam followers being shown in position;

Fig. 23 is a fragmentary detail showing the synchronizing gear train positioned for a 20 millisecond delay;

Fig. 24 is an enlarged fragmentary section through the oscillatable disk and associated retard and taken on line E i-2d of Fig. 4;

Fig. 25is a plan view of the synchronizing cam removed from the shutter with cam follower indicated in position for 5 millisecond retard;

' Fig. 26 is fragmentary detail of synchronizing switch removed from shutter.

My invention comprises broadly a shutter having-"blad'es of a symmetrical type movable in one direction only for opening and closing to make an exposure. In setting, the blades, are likewise moved'but in a reverse direction. Consequently I use diaphragm leaves which automatically cover the exposure aperture while the blades open and close during the setting movement. It further comprises mechanisms for operating the blades and diaphragm mechanism in synchronized relationship and for producing a shutter having a wide range of exposures of automatic duration in time as Well as mechanism for producing a manually controlled exposure.

'In thepreferred form of my invention shown in the drawings, the shutter may include the usual'typ'eof casing l having a central aperture EA' through which light passes in making an ex posure. The casing is provided with an upstandin'g'annular flange 2 and this flange is provided with a series of milled-out clearance portions 3, these portions being provided to permit certain parts to move through their full path of movement. As indicated in Figure 8, thebottom wall of theshutter 4 is annular in shape and it includes the usual rearwardly-extending tubular portion 5 normally threaded on the outside at Ii-for attachment to a support, and threaded on theinside at 'I to receive the usual lens mount. The shutter casing is divided roughly into two chambers 8 and 9 by means of a mechanism plate ID. This mechanism plate consists of a ringshaped' member having an upstanding flange ll of a generally cylindrical form and a forwardlyextending tubular member l2 internally threaded at l 3 to support the front lens Ll. The mechanism plate is secured in place by means of posts carried by the bottom of the shutter 4 and by means of screws passing through the mechanism plate Hi and into these posts. As this construction is customary, the posts and screws are not shown in the drawings.

Thelup'standing'flange 2 of the shutter casing is preferably provided with a rim M which may berabbeted at l5 if desired so as to receive a time-control earn it which is in the form of an annular ring and which is provided with a knurled edge H for turning the ring, a rabbet l8 and a flange l9. providing a space 20 in which a "flash camring 2i may turn. The rabbet l8 n: on

receives an edge 22 of an etched plate 23 which also is provided with ears 2 1 forming a part of a bayonet type latch, the slots or notches 25 in the tubular member l2 forming the other part of the bayonet latch. This etched plate, when placed on the front of the shutter, remains in a fixed position, although the time-control cam supported on its outer periphery, may turn freely a distance necessary to bring a pointer 26 carried by the time-control cam opposite any one of the shutter speed graduations 21 carried by the etched plate 23.

Generally speaking, the shutter mechanism is contained in the chamber 3 above the mechanism plate IG- and the shutter blades 29 and the diaphragmleaves I30 are carried in the chamber 9 beneath the mechanism plate.

The shutter blades 29 are of the symmetricallyshaped type which move only in one direction for opening and closing the exposure aperture 2. Each shutter blade, Figs. 2 and 3, 29 may bepivotally attached at Silto a blade ring 3! andeach shutter blade 29 may include a pin 32 extend,-

ing into a slot 33 in a second blade ring 34. Each.

blade ring 3i and 343 is, as shown in. Fig. 8, mounted to move in an arcuateuslot. blade ring 34 in a. slot 35 and blade ring 3| in aslot36 formed in transmitted to the opposite blade ring by means.

of a double-ended lever 31 as shown in Figs, 2

ring 3!. Thus, movement of ring 34. is simultaneously transmittedto blade ring 3| and as. theseblade rings move in opposite directions, the blades are moved in. one direction through their pathof movement, thus opening and closing the,

shutter aperture EA.

The blade ring 3! in this instance is the driven member and for this purpose the blade ring i-n-.

cludes an upstanding arm,v 43 which has twov radially and annularly offset contact surfaces 44.

and 45. These surfaces include a connecting. surface it which is rounded into the, contact sur-- face it-bythe curved wall 41.

There is a blade ring latch 48 pivoted on a. stud. MI and having a latching element 5|] lying, in the path of movement of a latching element. The latched 5| carried by the blade ring 34. position is shown in Fig. 2 and the unlatched position is shown in Fig. 3. The blade rings are latched when the shutter is set and before an exmilled in half to provide a shoulder 52. This pin moves in the direction shown by the arrowon the blade ring 34 in Fig. 13 when an exposure is to be made and the pin 25! may be engaged andv held by the latch 53 when the blades 29 are moved to an open position. Latch 53 is pivotally mount,-

ed on a studfi l carried by the mechanism plate.

and may be moved by a spring 255 .(Fig. 15) in e counter-clockwise direction about the pivot 54. This latch 53 and shoulder 52 are for temporarily holding the shutter with the shutter blades 29 in their wide-open position for exposures of less than the highest speed. Thi will be more fully g, described later.. 7

The driving mechanism or master member construction is best shown in Figs. 9 to 12 inclusive. The master member 55 is pivoted on a stud 56, this stud being carried by a lever 51 pivoted to the mechanism plate on a pivot 58. A spring 59 tends to turn this lever in the direction shown by the arrow in Fig. 9. As indicated in Fig. 14, a power spring 50 is attached to a pin 5| carried by the master member and to a stud 62 carried by the shutter casing. This spring always tends to turn the master member in the direction shown by the arrow in Fig. 9. The master member includes an upstanding flange 63 about which the spring 60 may be partially wrapped when the master member is in a position of tension or when it is set as shown in Fig. 9.

The master member 55 includes a flange 54 which carries a striking surface 65 which, in this instance, is shown as being a half-round pin. It likewise includes an upstanding flange 66, the function of which is to operate a shutter retard arm 6'! as shown in Fig. 14. The master member 55 in Fig. 9 is shown in its set position from which position it operates to make exposures from one second to 4 of a second to 1 second according to the setting. The arm 57 may be moved by means of a cam 68 to position the master member 55 for high-speed exposures of t of a second. Thus, the master member is swung bodily on the pivoted lever 51 between the high speed and the normal speed positions when the timecontrol cam 16 is moved.

The time-control cam I6 as shown in Fig. 22 consists of a ring movably mounted on the shutter casing as above described, this ring including a cam lug 68 which is the high-speed lug in that when the cam ring is moved until the pointer 26 is opposite the graduation 800 as indicated in Fig. 1, the cam follower 69, shown in Figs. and 22, is moved radially outwardly by the cam 68, thereby swinging the lever 5'! in a substantially radial direction against the action of its spring 59 and positioning the master member in the highspeed position of Fig. 10. The cam follower 69 is preferably made by milling off a portion of the head 10 of the stud 55 on which the master member 55 is mounted to swing. However, this is just a convenience in manufacture. From the cam shown in Fig. 22 it will be noticed that in the present embodiment of my invention the cam follower 69 is only moved when the lug 68 engages it and this only occurs when the highest speed V is to be used. In all other positions the cam follower is moved down against the concentric cam surface H in which the lever 51 is held in its normal speed position. That is, the position in which it will lie for all shutter speeds other than and including bulb.

It will be noticed from Fig. 5 that the master member 55 lies above the mechanism plate Ill and from Fig. 8 that the blade ring 3| which carries the driving arm 43 lies beneath the mechanism plate. From the small section A--A in Fig. 8 it will be noticed that this is accomplished by bending the arm 43 sharply upwardly at 12 and outwardly at 12' so that the radially-extending arm 43 may lie substantially in the plane of the master member 55 and in a position to be struck by the striking surface 65.

In order to set and release the shutter, I preferably provide a manually-operable lever 14 as shown in Fig. 6. This lever has a handle 15 which projects through a slot 16 in the upstanding flange 2 of the shutter casing (Fig. 14). Referring to Fig. 6, the manually-operable lever is an arcuate plate having arcuate slots 11 and 78 which slide about studs 19 and 58. Stud 58 also supports the master member carrying pivoted lever 51. The arcuate plate 14 carries a lug 80 which engages one end of a spring BI and one end of a second spring 82, the opposite end of spring 8| engaging an abutment 33 and the opposite end of spring 82 engaging an abutment 84. Spring 8| lies in a groove 85 in the mechanism plate l0 and spring 82 lies in a similar groove 86, the purpose of these two springs being to normally hold the manually-operated lever 14 in a normal position of rest indicated by R. in Fig. 4. This figure also shows the set position S of the lever 15 and the tripped position T since the single lever 14 is used to both set and trip the shutter, and serves both for a shutter setting lever and a trigger.

Referring again to Fig. 6, the lever 74 includes a releasing lug 81 formed upwardly from the lever and includes an offset arm 88 having an upturned flange 89. Lever 14 has an extended arm 90, the purpose of which will be later described. On the opposite end of the lever 14 there is a nose 9| which is positioned to engage and move the master member 55 through engagement with part 84 thereof, so as to swing the master member to its set position as shown in Fig. 6. At the same time an upwardly-extending lug 92 carried by the lever 14 may engage and turn the blade ring arm 43 so that it too will be moved to the set position shown in Fig. 6.

When the master member 43 is moved to its set position (Figs. 17 and 18) it may be held in this position by means of a master member latch element 94 pivoted on a stud 54 and pressed by a spring 255 in a clockwise direction so that the end 91 of this lever, which is a formed-down lug, may engage the flange 98 to retain the master member in its set position. When set for high speed the master member 43 travels substantially the same distance as for normal speeds but returns some distance before it is latched due to the position of the master member pivot 56 which has to be moved by arm 51. This difference in set position for high and normal speeds can readily be eliminated if a larger shutter casing is used. The latch member 94 at the opposite end is provided with an arm 99 which lies adjacent an oscillatable disk I00, this disk being freely movable about a stud I (H and including the spring I 02 tending to drive this disk in a clockwise direction. When this disk has been set, which is the position shown in Fig. 17, a tooth 1 E13 engages the end I04 of a tripping latch pivoted on stud l9 and normally turned by a spring IE6 in a counterclockwise direction. An arm m1 of this lever extends into the path of the upstanding lug 8'! of the manually-operable lever 14 and, consequently, when the handle 15 is moved from the rest position shown in Fig. 1'7 to the tripped position of Fig. 4, the lug 8! engages the arm [91, releasing the tooth I03, permitting the oscillatable member I00 to turn in the direction shown by the arrow in Fig. 17, so that tooth I98 will strike arm 99 and release the latch 9l98 so that the master member may turn in a counter-clockwise direction about its pivot 56. When this occurs, the pin 65 carried by the master member, which is the striking surface of the master member, will move the arm 43 in the manner above described to produce the time of exposure indicated by the pointer 26 and the graduation 21 in Fig. 1.

When any but the highest speed exposure is to. be made, the blade ring 34. swingsin-a clockwise direction under the impulse of the striking surface 65. against the contact. surface 45 of the blade ring arm 43. This movement swings the flat surface 52 of pin 25l into contact with the blade; ring holding latch 53; which latch is in the Fig. 13 position. Thus, movement of the blades is temporarily or momentarily arrested while the pin or striking surface 65 swingsacross the connecting surfaces. 41: and 416 of the blade ring arm 43- and just before movement of" the arm 431s resumed by the striking surface-'65 striking the contact surface 44, the flange 63iwi11 strike the end H0. of the latch 53 as indicated in Fig. 13-, moving'this latch out of engagement with the pin 25lso that when the striking surface 85 engages the contactsurface M the bladesv are free to move to their fully-closed position. The blades will be held in their fully-closed position because the striking surface 65 remains in contact with the master member arm 43. The blades therefore will; be held against movement after'an exposure.

In. order to hold the blades against movement before exposure, the latch shown in Fig. 3 is used. This. latch is spring-held in. the operative position shown in Figs. 2- and 3 and, as indicated in Fig. 2, engages thepoint 5I on the blade ring 34 when the shutter is in: its set position. Consequently, a jar will not tend. to open the set shutter blades. Fig. 7 shows the spring II-2 which positions a latch 48 and also indicates how this latch is released. When the arcuate plate M- is moved by the handle 15.:from its rest position R towards its tripped position T,"'the lever moves in a counter-clockwise direction. and a shoulder II3 on. this latch will-engage the upstandin lug H 4- turning member 48. in a counter-clockwise direction, thereby releasing the latch element 50' from. the latch element 5|. The relative positions of the shoulder I l3 and the lug I M are such that, the blade rings are released before the striking, surface 65' can move the necessary distance to move the blade ring arm 43.

The present embodiment of my shutter'does not include time exposure, that is, an exposure which. ismade by opening the shutter blades by depressing the trigger once and then by closing the-shutter blades by depressing the trigger a second time. It does, however, include a means for producing a manually-controlled and prolonged exposure of. the usual bulb type-that is; an exposure in which the trigger is depressed to openthe shutter blades and in which-the trigger is released to close them. To-obtain this bulb exposure, use is. made of the blade ring latch 53- bestshown in Figs. l3'to15 inclusive. This latch 5.3. isnormally held by the spring 255" against a stop pin H6. The latch includes an upstanding lug lllswhich. is so-positioned'that it may be engagedzby. a hook I it on the-bulb lever II'9 which is pivoted on the stud 58, also carryingthe master. member pivoted lever 51'. A spring I20 tends to turn the bulb lever in the direction shown by the arrow in Fig. 14. This movement can only be a-cccmplished when the upturned lug I2I can move a-limited distance in the cam slot I22 shown in Fig. 22. The rest ofthis cam slot: is a concentric groove I23 and when in this groove, the lug I2:I-; will hold-the bulb lever in-its inoperative position shown in Fig. 14'. However, as the speed cam control'ring isturned untilthe pointer 26* liesopposite. the graduation B,'the lug IZ'I' is brought into the widened cam'area I22 so that the spring I20 will thrust the hook IIB behind" the-lug II-Tofthe blade ring-latch. The blades will-be held in their fully-opened position because theulatch 53 can no longer be released by the flange 63 of the master member 43. Thus, the blades will be opened when the handle, serving as a trigger, I5 is depressed. When the handle 1'5 is released, the upstanding lug 81 moves away from arm ID! of the oscillatable member latch I 04, so that the spring Illfi can turn this latch member moving the arm I05 so that it will engage the upstanding lug I2I which also engages the cam slot I23. This will turn the bulb lever about its pivot 58 against its spring I20 causing the bulb lever I Hi to be moved back from its Fig. 1-5. to its Fig. 14 position. As soon as the hook I-IL8 releases the upstanding lug I ll the master member flange 63, through its engagement with the blade ring latch, releases this latch so that the master member can then close the shutter blades. The duration of a bulb exposure of course depends on the length of time that the handle I5 is depressed since the blades open when the handle I5 is moved from its R to its T position and closed when the handle moves from its T to-its R. position.

As above pointed out, the shutter blades 29openand close in moving in one direction. Consequently, it is necessary to close the exposure aperture while the opening and closing movement of the blades takes place in setting the shutter. Certain features of the diaphragm leaf closing mechanism are similar to the diaphragm shutter shown in my Patent 2,362,547, granted November 14, 1944, although the particular means for operating this mechanism is quite different.

Referring to Fig. 20, in the present embodiment of my invention I provide three diaphragm leaves I30; each of these leaves'being pivotally mounted on pins l3I' carried by the fixed diaphragm ring I32 also shown in Fig. 8. Each diaphragm leafis provided with a cam slot I33 which engages a pin I34 carried by an adjustable diaphragm ring I35, this ring including recessed portions I36 permitting the ring to move about the-pins I3I. The movable diaphragm ring l includes an upstanding pin I35 whichis engaged-by the slot [31in the end I38 of a lever I39, this lever being pivoted on a stud Mil carried by the mechanis plate Ill.

The lever I39 includes an offset arm MI having a pair of spaced upstanding ears Island I43, each. of which is slotted to receive and hold an end; I44, of a leaf spring I45, the opposite end of which engages an ear Mt on a pivoted lever I41, also mounted to turn on the stud M0. The lever I41: includes a flange I48 on the arm M9, this flange being positioned-to be engaged by the strikingisurface 850i the master member 43. This engagement only occurs when the master member is turning towards its-set position and the relative position of flange litland the-striking surface is so arranged that the diaphragm leaves will be opened after the shutter blades have openedand closed during the setting movement.

The lever l l'l'calries a latch element I5ll which may be engaged by a latch element I5! carried by-the bellscrank lever 552. This lever ispivoted on a stud: I53iand, as shown in Fig. 14, a spring I554 tends to turn this lever in the direction shown by the arrow in Fig. 20'and into a position to latch the lever Idl in a-position: to hold the shutter blades inan-openposition. The bell crank lever IE2 is provided with an upstanding ear I55, this ear lying in the path of movement of the blade ring arm-43 and particularly the cam end I 56*thereof. (Fig. 7).

Referringto Fig. 6, when lever 43 swings to the left with respect to this figure, it will strike part I55 rocking the bell crank lever I52 in a, clockwise direction so as to release the latch I50. When this is done, the diaphragm lever spring I51 (Fig. 20), through its engagement with a lug I58, will swing the lever I39 in a closing direction so that the diaphragm leaves will be completely closed shortly after the shutter blades have opened and closed to make an exposure.

The diaphragm leaf adjusting ring I35 is provided with a hook I60 which controls the total opening movement of the diaphragm leaves under the impulse of lever I41. Since there is a flexible connection or a lost motion connection between the lever I41 and the lever I39 because of the leaf spring I45, this spring will permit the diaphragm leaves to stop in any position determined by the pin I6I, which pin is controlled by movement of a diaphragm operating plate I64 best shown in Fig. 8. A diaphragm finger piece I65 extends from part I64 up across the upstanding flange 2 of the shutter casing, terminating in a diaphragm pointer I66 which, as shown in Fig. 1, can be brought opposite a suitable graduation I61 of the diaphragm scale arranged around the bottom of the etched plate 23. This diaphragm blade stop is similar to that shown in my patent although the means for actuating the diaphragm lever I39 is quite different.

There are a number of advantages in providing an oscillatable member I which can swing upon its stud IOI under the impulse of its own spring I02 for operating the shutter. First, such an oscillatable member permits a shutter in which the trigger or release lever can be so arranged that an excessively light pressure on the trigger will release the shutter and this occurs without any tendency to shake the shutter. Second, it provides a part co-acting with the release of the shutter in such a manner that movement of the oscillatable member always bears a definite relationship to the various positions of the shutter blades. Consequently, it forms an ideal member on which a switch can be placed to make a circuit which can be used for synchronizing flash lamps. Third, it adds but little to the necessary force required for setting the shutter since the flange 39, through its engagement with a tooth I65, turns the oscillatable member as the handle 15 is moved to set the master member and the shutter blades.

If desired, my shutter may be equipped with a connecting plug I10, Fig. 4, having one terminal I1I connected to an insulated wire I12 and having a second terminal I13 connected to a wire I14 grounded to the casing. The wire I12 may be passed around the flange 2 of the shutter casing in any convenient manner but preferably in a shallow groove I15, and it may be connected to a, terminal I16 (Fig. 4) forming one element of a switch. The other element I11 of the switch is carried by a bell crank lever I18. This lever, as shown in Fig. 4, carries a pivot I19 on which a latch element I80 is mounted to turn, a spring I8I normally holding a lug I82 in the position shown in Fig. 4 against the bell crank lever. The opposite end I83 of the bell crank lever carries a gear segment I84, meshing with a pinion I85, carrying a flywheel or weight I86.

Each time the oscillatable member I00 turns in a clockwise direction, a tooth I81 may engage latch-arm I80 so as to turn the bell crank lever to control the speed of operation of the oscillatable member I00. The degree of engagement of this retarding member with the oscillatable member I00 may be controlled by the cam ring shown in Fig. 25. This ring H is provided with a step cam comprising three steps-490, I9I, and I92. A pin I93 carried by the bell-crank lever I98 engages these cams and controls the time when the switch I11I16 makes contact relative to the full, open position of the blades. As indicated in Fig. 1, there is a pin I95 extending through a slot I96 in the etched plate 23. This pin may be moved opposite graduations I91 indicating the required millisecond delay for various different flash bulbs. For instance, the No. 5 flash bulb happens to require a five-millisecond delay and since the pin I95 is set at 5 in Fig. 1, the pin I93 in Fig. 25 being similarly positioned will give the required delay so that the flash lamp will reach its full brilliance while the shutter blades are fully opened.

The pin I93 is carried by the insulated section I98 which can be swung about the stud I99 on which the bell crank lever I18 is mounted. Thus, movement of the cam 2I controls the position of the insulated segment I18 and with it the contact I16 relative to the contact I11. The latch I carries an upstanding lug 200, this lying in the path of pin 20I on the flash-adjusting cam 2| and contacting with it when the contact ring is adjusted to the zero position shown in Fig. 1. In this position the latch I80 will be rocked against the action of its spring I8I into an inoperative position so that the switch mechanism may not be moved at all when the synchronizing cam 2I is set to the zero position.

While it is possible to obtain the extremely high speeds with the single spring 60 driving the master member, if desired, an additional spring can be brought into play for the highest speed exposure here shown as of a second. This is accomplished in the manner shown in Figs. 18 and 19. On the master member pivot 56 I provide a lever 2 I0 which is mounted to freely turn on the pivot 56. One end of spring 2H engages lever 2I0 and is coiled at 2I2 about the post 56. The arm 2 I0 may be engaged by one of the steps of cam 2 I3 so that when the pointer 26 is brought opposite the 800 on the scale 21, the lever 2I0 will be turned to the position shown in Fig. 18, while at the same time portion 68 of the cam will hold the cam follower 69 in its raised or high-speed position. Thus, spring 2I2 is added to spring 60 for the highest speed exposure only by turning the speed cam ring so that the cam follower 69 swings the pivoted lever in a generally radial direction to its high-speed position. When the cam follower 69 is allowed to return to cam surface 1I, spring 2I2 is unwound so that it is no longer operative to assist spring 60. In many cases it may be found that this additional spring is entirely unnecessary but it has been described as a useful addition to the master member described above.

The stepped cam surface M3 is positioned to engage an upstanding pin 220 carried by arm 61 pivoted on a stud. 22L A spring 222 tends to turn this arm in the direction shown by the arrow in Fig. 4 so that the pin 220 resting against the stepped cam 2I3 limits the degree of engagement of this arm with the master member lug 60. Gear segment 223 meshes with a pinion 224 of a train of gear terminating in a starwheel 225 with which a pallet 226 may be engaged. The pallet 220 is pivoted at 221 upon a lever 228 pressed by a spring 229 into a starwheel-engaging position, However, the pin 221 extends upwardly 11 into the cam slot 230 as indicated in Figure 22, so that the starwheel is only engaged for some of the more prolonged automatic exposures.

When setting the shutter it is necessary to move the handle 15 fully to the set position S. The setting movement of the manually operable lever 14 causes nose 9! to engage and move the master member 64 and the lug 92 on lever 14 to move the blade rings through arm 43. Also striking sur-- face 65 of the master member must strike flange M8 to open the diaphragm leaves 130 and latch them open by latch Illl5l. Since the diaphragm leaves must be opened only after the shutter blades open andclose and the timing is close, full setting is important.

A latch is therefore provided which will make it necessary to fully set the handle 15 through the last and critical part of its travel. Referring to Fig. 6 shows the extreme end 235 of the arcuate lever M as constituting one latch element, and the downwardly extending spring 236 the other latch element. Spring 236 has a downwardly turned flange 231' fastened on arm 238 of the oscillatable member latch lever M15 as by rivets 235. In Fig. 6 D shows the critical final setting movement. If not fully set and the setting lever returns before reaching this last movement, no harm is done.

When handle 15 is moved towards its set position S, Fig. 16, the cam surface E li! swings lever I05 to the left in Fig, 16 so flange 231 lies below latch 235 and consequently any reverse movement after passing the spring latch 23%; is prevented. Further movement of handle 15 swings the oscillatable member lllEl so that cam 240 passes lever I05 and as soon as tooth I03 snaps past latch edge HM the shutter, as well as the oscillatable member are all completely set and are now ready for exposure. This is a safety feature, not essential but useful.

In order to visualize the size of my present shutter constructed in accordance with a preferred embodiment of my invention, as shown in the drawings, it might be pointed out that the view in Fig. 4 is approximately four times the actual size of this shutter which will be known as a No. 1 shutter. It is probable that there will beat least one smaller size and several larger sizes, but the first shutter is being considered in the No. 1 size which has a clear exposure aperture of .765 inch. Throughout the drawings applicant has endeavored to closely follow the various parts to actual scale although in some instances, and particularly where springs are shown, it is impossible to show them of the correct thickness and still retain the type of showing required in Patent Office drawings. In many of the views, parts have been omitted in an eiiort to clearly show the construction of other parts. I have been able to obtain, with the above-described shutter mechanism, an exposure of of a second with a clear exposure aperture of .765 inch using the standard system of measuring effective exposures. It it undoubtedly possible to obtain considerably faster exposures at some sacrifice of durability because I have provided extremely high speeds utilizing only springs of the type which are now in use in standard shutters on the market without increasing the tension on these springs. moving parts necessary for driving the shutter blades from the master member to a minimum. In addition, I have provided a shutter in which the release requires only a very light or delicate pressure on the trigger, thereby noticeably re- This is accomplished by reducing the ducing vibration of the shutter which frequently occurs from relatively heavy trigger pressure. The master member is small and of comparatively light weight and it acts directly upon an arm carried by one of the blade rings so that additional intermediate parts heretofore rather generally used have been omitted.

The master member has a striking surface which moves through an arcuate path, this path being changed for normal speed and high speed exposures. The length of the striking surface of the master member is only approximately one-third the length of the blade ring arm measuring each from its own center of rotation. The master member striking surface travels about twice as many degrees about its pivot before striking the contact surface 44 for high speed than it does for striking surface 35 for normal speed in the embodiment of my invention illustrated in the drawings. This data is by way of illustration since it is obvious that by altering the size of the parts these various ratios can be readily changed. However, I have found the above data desirable in an extremely compact shutter of the type shown in the present embodiment of my invention.

The operation of my improved shutter is extremely simple, although a description of the various movements of the parts which take place inside the shutter casing is necessarily rather long. Assuming the shutter is in its normal condition of rest after an exposure has been made, as shown for instance in Fig. 4, the handle 15, which serves both as a trigger and a setting lever, is in its position of rest R. The operator selects the required speed by turning the narrow ring speed-adjusting cam 15 until the pointer 26 is brought opposite a graduation 21 on the shutter cover plate 23. If the diaphragm opening has not been selected, the lever I66 may be moved to the required diaphragm opening graduation it? also on the cover plate 23. If a flash exposure is not required, the knob I may be moved to the graduation zero on the scale Hill on the shutter cover plate.

The operator then moves handle 15 from its rest position R to its set position S. This movement accomplishes a series of different things. First, referring to Fig. 6, the most 9! of the lever 74 strikes part 64 of the master member; turning it to its set position and winding up the driving spring 693. Second, the lug an on the lever 'M moves the blade ring arm 53 about its center of rotation causing the shutter blades to open and:

close. Third, the striking member 65 on the master member engages the lever M9 swinging it to tension spring M5, this spring in turn, shown in Fig. 20, overcoming spring E5?! of the diaphragm leaf lever 13.! and causing the diaphragm leaves to open to the preselected stop as controlled by the pin 16! and the hook lbll on the diaphragm leaf-adjusting ring I35. Fourth, the movement of the lever M, as indicated in Fig. 6, causes flange 89 to engage the oscillatable member or starwheel tooth i turning this memberwhile tensioning its spring 66 2. As all these movements are accomplished, various latches drop into position to hold the parts in their set position.

The master member is held in its set position by means of the latching flange 91 engaging the master member flange 98. The shutter blade arm 43 is held in its position by means of the latch 50 engaging the blade ring latch 5|. The oscillatable member I00 is held in its latched position by means of the end M14 of the latch 13 I05, dropping behind the tooth I03 on the oscillatable member. All of the parts are positioned automatically, and there is an additional safety spring latch 236 adapted to momentarily hold the latch element 235 of the lever 14 against backward movement until all of the parts have been moved. and latched in their set position. The shutter is now ready for an exposure and it should be noticed that as soon as the full setting stroke has been accomplished, the release of the handle I5 causes the spring 86 to return the setting lever from its S position to its rest or R position shown in Fig. 1 from which position the handle I5 may serve as a trigger to release the shutter. With the parts set as indicated in Fig. 14, (which shows the shutter set but which does not show the shutter handle I5 released and returned to its R position) the trigger may be depressed moving the handle I5 from its R position to its tripped position T. This movement causes the lug 8! of lever M to strike arm I'I of lever I turning this oscillatable member latch in a clockwise direction and releasing the tooth I03 from the latch I04. The oscillatable member I00 turning under the power of its own spring will cause tooth I08 to strike the end 99 of the master member latch releasing the latch element 9'! from the shoulder 98 and permitting the master member to turn. As the master member turns, since the shutter has been set for a normal speed exposure, the striking surface 65 will first engage the contact surface 45 swinging the blade ring 3| in a counter-clockwise direction while blade ring 34 moves in an opposite direction. i

The striking member will ride over faces 47 and 45 during which time the blade rings will momentarily remain stationary because of the engagement of latch 53 and pin 25L However, when the striking surface 65 engages contact surface 44 flange 63 of the master member releases the latch 53 and as the pin 65 engages the surface 44 the latch, having been just released, permits the shutter arm 43 to be again driven to close the blades. The shutter blades will be held in a closed position because of the pressure of the striking member 65 on the arm 43.

If the shutter should have been set for its high speed exposure, the master member would be given an additional impetus because the spring 2I2 carried by the lever H0 is tensioned when the speed-adjusting cam is moved. Thus, not only is the master member driven under higher spring power for the top speed exposure but, in addition, the striking surface 65 thereof travels a greater distance since it directly engages the surface M of the blade ring arm 43 and swings it in one continuous, smooth, uninterrupted movement to open and close the blades. During this movement the blade ring latch 53 is held out of its operative position.

If the shutter had been set for bulb exposures, the latch 53 would be held in by the bulb lever H9 through the engagement with the upstanding lug II'I on the blade ring latch, so that it would require an upward movement of the handle 15 from its T position to its R position in order for the shutter blades to close.

If a synchronized flash is to be used, the knob I85 is set to the required graduation on scale I91 and the shutter is actuated exactly as before, except that since the oscillatable member 00 has a speed definitely related to the opening and closing of the shutter leaves, the required millisecond delay can be accurately obtained.

14 If the flash is not to be used, the knob I is turned to the zero graduation so that the flash retard mechanism is then inoperative.

While I have described a preferred form of my invention, it is obvious that many variations can be made from the specific structure shown in the drawings and described in the above specification without departing from my invention as defined in the following claims.

What I claim is:

1. In a camera shutter of the type including an apertured casing, two interconnected blade rings movably mounted in the casing, shutter leaves oper-atively connected to the blade rings for movement to make an exposure through the shutter casing aperture, the combination with said blade rings, of a master member, means for producing exposures of different durations including a pivoted levermovably carrying the master member, a striking surface on the master member having an arcuate path of movement, means for setting and releasing the master memher, an arm carried by a blade ring having different contact surfaces thereon and positioned to co-act with the master member striking surface, and means for moving the pivoted lever to select the contact surf-ace of the arm to be struck by the striking surface of the master member, to operate the blade rings to make an exposure.

2. In a camera shutter of the type including an apertured casing, two interconnected blade rings movabl mounted in the casing, shutter leaves operatively connected to the blade rings for movement to make an exposure through the shutter casing aperture, the combination with said blade rings, of a master member, means for producing differently-timed exposures including a pivoted lever movably carrying the master member, a striking surface on the master member movable through an arcuate path, means for setting and releasing the master member, an arm carried by a blade ring having different contact surfaces thereon spaced from the center of rotation of the blade ring and lying in the arcuate path of movement of the striking surface on the master member, and means for moving the pivoted lever in a generally radial direction to select the contact surface of the arm to .be struck by the striking surface of the master member, to operate the blade rings to make an exposure.

3. In a camera shutter of the type including an apertured casing, two interconnected blade rings movably mounted in the casing, shutter leaves operatively connected to the blade rings for movement to make an exposure through the shutter casing aperture, the combination with said blade rings, of a master member, means for producing differently-timed exposures including a pivoted lever movably carrying the master member, a striking surface on the master member movable through an arcuate path, means for setting and releasing the master member, an arm carried by a blade ring having different contact surfaces thereon spaced both radially and circumferentiall relative to the center of rotation of the blade rings and also positioned to co-act with the master member striking surface, and means for moving the pivoted lever in a generally radial direction to select the contact surface of the arm to be struck by the striking surface of the master member and to determine the travel of the striking surface before striking the selected contact surface, to operate the blade rings to make an exposure.

4. In a camera shutter of the type including an apertured casing, two interconnected blade rings movably mounted in the casing, shutter leaves operatively connected to the blade rings for movement to make an exposure through the shutter casing aperture, the combination with said blade rings, of a master member, means for producing differently-timed exposures including a pivoted lever movably carrying the master member, a striking surface on the master member movable through an arcuate path, means for setting and releasing the master member, an arm carried by a blade ring having different contact surfaces thereon arranged in a plurality of steps extending in a general direction away from the center of rotation of the master member and positioned to co-act with the master member striking surface, and means for moving the pivoted lever to carry the striking surface on the master member into a position from which it may be moved through a path to engage one of said steps to select the contact surface of the arm to be struck b the striking surface of the master member, the steps and striking surface being relatively p sitioned to cause said striking surface to move a different distance before striking a contact surface for each different step, to operate the blade rings to make an exposure.

5. In a camera shutter of the type including an apertured casing, two interconnected blade rings movably mounted in the casing, shutter leaves operatively connected to the blade rings for movement to make an exposure through the shutter casing aperture, the combination with said blade rings, of a master member, means for producing differently-timed exposures including a pivoted lever movably carrying the master member, a striking surface on the master member movable through an arcuate path, means for setting and releasing the master member, an arm carried b a blade ring having different contact surfaces thereon, one positioned further away from the center of rotation of the master member than the other whereby the effective length of said arm carried by the blade ring may be varied, said blade ring arm being positioned to co-act with the striking surface of the master member, and means for moving the pivoted lever to select the contact surface of the arm to be struck by the striking surface of the master member and to vary the mechanical advantage of the master member striking surface relative to the blade ring lever, the centers of rotation of the blade ring and master member being selected to cause the striking surface of the master member to successively engage the contact surfaces on the blade ring arm when the pivoted arm is moved to one position, to operate the blade rings to make an exposure.

6. A shutter according to claim 1 in which there is a latch movable to and from a position to stop movement of the blade rings before movement of the blade rings has been completed.

7. A shutter according to claim 1 in which there is a latch movable to and from a position to stop movement of the blade rings before movement of the blade rings has been completed, said latch including a nose lying in the path of the master member when in a latching position to be released thereby before said master member completes its movement.

8. A shutter according to claim 1 in which there is a latch movable to and from a position to stop movement of the blade rings before movement of the blade rings has been completed, and means for holding said latch in an inoperative position 16 when the master member carrying lever is in one position.

9. In a camera shutter of the type including an apertured casing, two interconnected blade rings movably mounted in the casing, shutter leaves operatively connected to the blade rings for movement to make an exposure through the shutter casing aperture, the combination with said blade rings, of a master member, a pivoted lever movably carrying the master member, a striking surface on the master member movable through an arcuate path, an arm carried by a blade ring having different contact surfaces thereon lying in the arcuate path of movement of the striking surface of the master member, and means for moving the pivoted lever to select the contact surface of the arm to be struck by the striking surface of the master member, a latch for the master member for holding the latter set in all positions of the pivoted lever carrying the master member, and means for releasing said latch.

10. In a camera shutter of the type including an apertured casing, two interconnected blade rings movably mounted in the casing, shutter leaves operatively connected to the blade rings for movement to make an exposure through the shutter casing aperture, the combination with said blade rings, of a master member, means for producing differently-timed exposures including a pivoted lever movably carrying the master member, a striking surface on the master member movable through an arcuate path of movement determined by the pivoted lever, an arm carried by a blade ring having different contact surfaces thereon movable through an arcuate path of movement and positioned to coact with the striking surface on the master member, and means for moving the pivoted lever to select the contact surface of the arm to be struck by the striking surface of the master member, a latch for holding the master member in a set position, an operating lever movable in one direction for moving the master member to its set position, a releasing mechanism for the master member latch including a releasing lever in the path of movement of the operating member positioned to be operated thereby toward the end of the movement of the operating lever in a direction opposite to that of the movement of the operating lever is setting the shutter.

11. In a camera shutter of the type including an apertured casing, two interconnected blade rings movably mounted in the casing, shutter leaves operatively connected to the blade rings for movement to make an exposure through the shutter casing aperture, the combination with said blade rings, of a master member, means for producing differently-timed exposures including a pivoted lever movably carrying the master member, a striking surface on the master member movable through an arcuate path determined by the pivoted lever, an arm carried by a blade ring having different contact surfaces thereon and moving through an arcuate path intersecting the arcuate path of movement of .the striking surface of the master member as determined by the pivoted lever, and means for moving the pivoted lever to select the contact surface of the arm to be struck by the striking surface of the master member, a latch for holding the master member in a set position, an operating lever movable in one direction for moving the master member to its set position, a releasing mechanism for the master member latch including a releasing lever in the path of movement of the operating member positioned to be operated thereby toward the end of the movement of the operating lever in a direction opposite to that of the movement of the operating lever in setting the shutter, said releasing mechani including an oscillatable releasing disk, a spring for driving said disk in one d ection, and means carried by the operatig h. e for setting the releasing disk.

12. In a camera shutter of the type including an apertured casing, two interconnected blade rings movably mounted in the casing, shutter leaves operatively connected to the blade rings for mov c. .ent to make an exposure through the shutter casing aperture, the combination with said blade rings, of master men her, a pivoted lever movably carrying the master member, a striking surface on the master member, an arm carried by a blade ring having difierent contact surfaces thereon, and means for moving the pivoted lever to select the contact surface of the arm to be struck by the striking surface of the master latch. for holding the master member in a set position, an operating lever incl ding an operating handle movable in one direction. for moving the master member to its set position, a releasing mechanism for the master member latc including a releasing le er in the path of movement of the operating nber positioned to be operated thereby towo d the end of the movement of the operating lever in a direction opposite to that of the movement of the operating lever in setting the shutter, said releasing mechanism including an oscillatable releasing disk, a spring for driving said disk in one direction, and means carried by the operat g handle for setting the releasing operating handle being adapted to ening disk in moving in one direction, and

means normally positioning the operating andle in a position between the releasing and setting positions.

13. In a camera shutter of the type including an apertured casing, two interconnected blade movably mounted in the casing, shutter leave operatively connected to the blade rings for movement to make an exposure through the shutter casing aperture, the combination blade rings, of a master member, producing variably timed exposures r a striking pin carried thereby movable an arcuate path, a pivotal mount for the ter member about which the striln'ng m mber turn. an arm carried by a blade 1" cent the master member movable through arcuate path and positioned to coact with the striking pin moving through its path, the length of the arm from the center of rotation or the blade ring being appromat v three times great the distance st 'ng pin of the master member from the center of rotation of the master member. member being so situated that said I strike and drive the said blade e arm contacting with substantially the end id or and for altering the posi- (i011 of striking contact with said arm com-- movable support, said pivotal mount for the master member being carried by the support, and means for setting and releasing the master member.

14. In a camera of the type including an apertured casing two interconnected blade rings 18 movably mounted in the casing, pivoted shutter leaves operatively connected to the blade rings for movement to make an exposure through the shutter casing aperture, the combination with said rings, of a master member, means for producing exposures of different durations in cluding a pivoted lever pivotally carrying the master member, a striking pin ca :ied by the master member swingable through an arcuate 10 p th of movement about the master member pivot, means for setting and releasing the mastcm an arm carried by a blade ring id ig into the path of movement of the be pin and positioned to co-act therewith, ovement of said pivoted lever carrying the pivoted master member changing the angular travel of the striking pin before striking said ring arm to move said arm for Operating the shutter blades at different speeds. or 15. In a camera of the type including an apertured two interconnected blade rings movably mounted in the casing, pivoted shutter loaves operatively connected to the blade rings for movement to make an exposure through the shutter casing aperture, the combination with id blade rings, of a master member, means for oducing exposures of different durations ina pivoted lever pivotally carrying the member, a striking pin carried by the member swingable through an arcuate path of movement about the master member pivot, means for setting and releasing the master nnber, an arm carried by a blade ring extending to the path of movement of the striking pin 35 a d positioned to co-act therewith, means for moving the pivoted lever to move the pivoted master member to different positions in a general radial direction with respect to the center of r tation of the blade ring arm, whereby the striklo carried by the master member may operate blade ring arm with different mechanical advantage at different positions of said pivoted lever.

16. The camera shutter defined in claim 14 4,5 characte'iaed by a striking pin and blade ring being positioned to vary the angular travel the striking pin before engaging and driving the blade ring arm from approximately six degrees at one extreme position to approximately eighteen 50 degrees at the opposite extreme position.

17. The shutter defined in claim i l characterized by the arm carried by a blade ring extending i a generally radial direction and having two -gularly offset generally radial striking surfaces, the striking pin carried by the master member g movable on the pivoted arm in a generally red 1]. direction. along said arm to strike either of two striking surfaces for producing differently timed exposures. 60 i8. ihe shutter defined in claim 14 characterized by the arm carried by a blade ring extending a generally radial direction and having two angularly offset generally radial striking surfaces, and the striking pin carried by the master mem- 35 her being movable on the pivoted arm in a genradial direction, the angular offset of the i L erally radial blade ring arm surfaces rela- 've to the positions of the striking pin altering is angular travel. of the latter about its pivot ore striking said blade ring arm for making and the striking pin carried by the master member being movable on the pivoted arm in a generally radial direction, the angular ofiset of the two generally radial blade ring arm surfaces relative to the positions of the striking pin altering the angular travel of the latter about its pivot before striking said blade ring arm so that said striking pin may travel approximately three times the angular distance before striking said blade ring arm in making one exposure over that traveled for making the other exposure.

20*. The shutter defined in claim 14 characterized by the arm carried by a blade ring extending in a generally radial direction and having two angularly offset generally radial striking surfaces, and the striking pin carried by the master member being movable on the pivoted arm in a generally radial direction along said arm to strike either of said two striking surfaces for producing differently timed exposures, and means, associated with one of said two striking surfaces for retarding movement of the master member before said master member completes its movement.

21. In a camera of the type including an apertured casing two interconnected blade rings mov-- ably mounted in the casing, pivoted shutter leaves operatively connected to the blade rings for movement to make an exposure through the shutter casing aperture, the combination with said blade rings, of a master member, means for producing exposures of dii ferent durations including a pivoted lever pivotally carrying the master memher and movable between. two positions selected to move the master member substantially radially of the center of rotation of the blade rings, a striking pin carried by the master member and having two adjacent arcuate paths of movement according to the position of the pivoted lever, an arm extending in a generally radial direction from a blade ring, said striking pin, when in one position, coacting with one portion of said blade ring arm for moving said arm and when in the other position coast-- ing with another portion of said blade ring arm radially spaced from said first mentioned portion l,

of said arm whereby said striking pin may operate said blade ring arm at two different mechanical advantages.

22. In a camera shutter of the type including an apertured casing, pivotally mounted shutter blades mounted for movement to open and close the aperture to make an exposure, mechanism for moving the shutter blades, the combination with said shutter blades, of a master member for operating said mechanism to move the shutter blades, a latch element carried by the master member, a latch carried by the casing and engageable with the latch element on the master member for holding said master member in a set position, an oscillatable shutter releasing member, a spring moving said releasing member in a releasing direction, a lug carried thereby to engage and release the latch carried by the casing and holding the master member against movement, a shutter trigger, a second latch for holding the oscillatable shutter releasing member in a tensioned position, said second latch lying in the path of and being operable by said shutter trigger whereby operation of said trigger may release the oscillatable shutter releasing member for movement under its own spring to turn and release the master member holding latch.

23. In a camera shutter of the type including an. apertured casing, pivotally mounted shutter blades mounted for movement to open and close the aperture to make an exposure, mechanism for moving the shutter blades, the combination with said shutter blades, of a master member for operating said mechanism to move the shutter blades, a latch element carried by the master member, a latch carried by the casing and engageable with the latch element on the master member for holding said master member in a set position, an oscillatable shutter releasing member, a spring moving said releasing member in a releasing direction, a lug carried thereby to engage and release the latch carried by the casing and holding the master member against movement, a shutter trigger, a second latch for holding the oscillatable shutter releasing member in a tensioned position, said second latch lying in the path of and being operable by said shutter trigger whereby operation of said trigger may release the oscillatable shutter releasing member for movement under its own spring to turn and release the master member holding latch, the lug on the oscillatable member being positioned relative to the latch engaging the master member so as to travel a predetermined distance before releasing said master member holding latch.

24. In a camera shutter of the type including an apertured casing, pivotally mounted shutter blades mounted for movement to open and close the aperture to make an exposure, mechanism for moving the shutter blades, the combination with said shutter blades, of a master member for operating said mechanism to move the shutter blades, a latch element carried by the master member, a latch carried by the casing and engageable with the latch element on the master member for holding said master member in a set position, an oscillatable shutter releasing memher, a spring moving said releasing member in a releasing direction, a lug carried thereby to engage and release the latch carried by the casing and holding the master member against movement, a shutter trigger, a second latch for holding the oscillatable shutter releasing member in a tensioned position, said second latch lying in the path of and being operable by said shutter trigger whereby operation of said trigger may release the oscillatable shutter releasing member for movement under its own spring to turn and release the master member holding latch, the lug on the oscillatable member being positioned relative to the latch engaging the master member so as to travel a predetermined distance before releasing said master member holding latch, and means for varying the speed of movement of the oscillatable shutter releasing member.

25. In a camera shutter of the type including an apertured casing, pivotally mounted shutter blades mounted for movement to open and close the aperture to make an exposure, mechanism for moving the shutter blades, the combination with said shutter blades, of a master member for operating said mechanism to move the shutter blades, a latch element carried by the master member, a latch carried by the casing and engageable with the latch element on the master member for holding said master member in a set position, an oscillatable shutter releasing member, a spring moving said releasing member in a releasing direction, a lug carried thereby to engage and release the latch carried by the casing and holding the master member against movement, a shutter trigger, a second latch for holding the oscillatable shutter releasing member in a tensioned position, said second latch lying in the path of and being operable by said shutter'trigger whereby operation of said trigger may release the oscillatable shutter releasing member for movement under its own spring to turn and release the master member holding latch, the lug on the oscillatable member being positioned relative to the latch engaging the master member so as to travel a predetermined distance before releasing said master member holding latch, a gear train, means for delaying movement of the oscillatable shutter releasing member after its release by the shutter trigger, including a tooth carried by the oscillatable member engaging said gear train.

26. In a camera shutter of the type including an 'apertured casing, pivotally mounted shutter blades mounted for movement to open and close the aperture to make an exposure, mechanism for moving the shutter blades, the combination with said shutter blades, of a master member for operating said mechanism to move the shutter blades, a latch element carried by the master member, a latch carried by the casing and en- 'gageable with the latch element on the master member for holding said master member in a set position, an oscillatable shutter releasing member, a spring moving said releasing member in a releasing direction, a lug carried thereby to engage and release latch carried by the casing and holding the master member against movement, a shutter trigger, a second latch for holding the oscillatable shutter releasing member in a tensioned position, said second latch lying in the path of and being operable by said shutter trigger whereby operation of said trigger may release the oscillatable shutter releasing member for movement under its own spring to turn and release the master member holding latch, the shutter trigger being movably mounted on the shutter casing, for movement to and from a releasing position, a lug carried by the trigger and en" gageable with the spring operated shutter releasing member to move this member against its spring and to a position in which it may be held in a set position by said second latch when said shutter trigger is moved from a releasing direction.

27. In a camera shutter of the type including an apertured casing, pivotally mounted shutter blades mounted for movement to open and close the aperture to make an exposure, mechanism for moving the shutter blades, the combination with said shutter blades, of a master member for operating said mechanism to move the shutter blades, a latch element carried by the master member, a latch carried by the casing and engageable with the latch element on the master member for holding said master member in a set position, an oscillatable shutter releasing member, a spring moving said releasing member in a releasing direction, a lug carried thereby to engage and release the latch carried by the easing and holding the master member against movement, a shutter trigger, a second latch for holding the oscillatable shutter releasing member in a tensioned position, said second latch lying in the path of and being operable by said shutter trigger whereby operation of said trigger may release the oscillatable shutter releasing member for movement under its own spring to turn and release the master member holding latch, the shutter trigger being movably mounted on the shutter casing for movement to and from a releasing position, a lug carried by, the trigger and engageable with the spring-operated shutter releasing member to move this member rings mounted in the casing, shutter leaves operatively connected to the blade rings to make an exposure through the shutter casing aperture,

the combination with said blade rings, of mechanism for driving said blade rings including an arm extending in a generally radial direction from a blade ring and movable through a fixed arcuate path, a striking surface on the arm including a pair of angularly and radially spaced faces connected by a generally concentric face, a pivoted lever, a master member pivotally carried thereby, and including a striking pin movable through an arcuate pa-th crossing the arcuate path of said blade ring arm, means for setting and releasing the master member, said pivoted lever having different positions for positioning the master member striking pin in different operative positions to co-act with the blade ring arm, in one position of said arm positioning the master member striking pin for engaging one of said angularly and radially spaced faces, and in another position of said arm positioning the master member striking pin for engaging one angularly and radially spaced faces after the other, moving between said faces across the generally concentric face.

29. In a camera shutter of the type including an apertured casing, two interconnected blade rings mounted in the casing, shutter leaves operativcly connected to the blade rings to make an exposure through the shutter casing aperture, the combination with said blade rings, of mechanism for driving said blade rings including an arm extending in a generally radial direction from a blade ring and movable through a fixed arcuate path, a striking surface on the arm including a pair of angularly and radially spaced faces connected by a generally concentric face,

a pivoted lever, a master m mber pivotally carried thereby, and including a striking pin movablethrough an. arcuate path crossing the arcuate path of said blade ring arm, means for setting and releasing the master member, said pivoted lever having two positions for positioning the master member striking pin in two operative positions to co-act with the blade ring arm, in one position of said arm positioning the master member striking pin for engaging one of said angularly and radially spaced faces, and in another position of said arm positioning the master member striking pin for engaging one angularly and radially spaced faces after the other, moving between said faces across the generally concentric face.

30. A shutter as defined in claim 29 characterized by the pivoted lever positioning the master member striking pin to clear one angularly and radially spaced face and the generally concntric iace'in moving through the arcuate path and into striking engagement with one angularly and radially spaced face for high speed exposures.

31. A shutter as defined in claim 29 characterized a gear delaying mechanism including a operating arm positioned to engage and retard the master member striking pin when said pin is moving between said angularly and radially spaced faces and across said generally concentric face.

32. A shutter as defined in claim 29 characterized by a gear delaying mechanism including a gear operating arm positioned to engage and retard the master member striking pin when said pin is moving between said angularly and radially spaced faces and across said generally concentric face, and means for varying the position of said gear operating arm relative to the arcuate path of said striking pin moving across said generally concentric face.

33. A shutter as defined in claim 29 characterized by a gear delaying mechanism including a gear operating arm positioned to engage and retard the master member striking pin when said pin is moving between said angularly and radially spaced faces and across said generally concentric face, and manually operable means to position said gear operating arm for engagement by said striking pin during all or a part of the movement of said striking pin across said generally concentric face of said blade ring arm.

34. In a camera shutter of the type including an apertured casing, two interconnected blade rings mounted in the casing, shutter leaves operati-vely connected to the blade rings to make an exposure through the shutter casing aperture, the combination with said blade rings, of mechanism for driving said blade rings including an arm extending in a generally radial direction from a blade ring and movable through a fixed arcuate path, a striking surface on the arm including a pair of angularly and radially spaced faces connected by a generally concentric face, a pivoted lever, a master member pivotally carried thereby, and including a striking pin movable through an arcuate path crossing the arcuate path of said blade ring arm, means for setting and releasing the master member, said pivoted lever having different positions for positioning the master member striking pin in different operative positions to co-act with the blade ring arm, in one position of said arm positioning the master member striking pin for engaging one of said angularly and radially spaced faces, said master member including a spring, means for tensioning and releasing the master member, a second master member spring, a manually adjustable member for selecting exposures, and means carried by said member for moving the pivoted lever carrying the master member and its striking pin to a high speed position in which said striking pin is positioned to engage only one of said angularly and radially spaced faces, said manually adjustable member also tensioning the second master member setting spring.

35. A shutter as defined in claim 34 characterized by the second master member spring being anchored on a lever pivoted coaxially with the master member.

36. A shutter as defined in claim 34 characterized by the second master member spring being anchored on a lever pivoted coaxially with the master member and on the pivoted lever carrying the master member, whereby said manually adjustable member may move both the master member and wind the second master member spring simultaneously.

37. In a camera shutter of the type including an apertured casing, pivotally mounted shutter blades mounted for movement to open and close the aperture to make an exposure, mechanism for moving the shutter blades, the combination with said shutter blades, of a master member for operating said mechanism to move the blades, a latch element carried by the master member, a latch carried by the casing for engaging and releasing the master member latch, an oscillatable shutter releasing member including an car a spring for moving the oscillatable member in a releasing direction and causing said ear to release the master member latch, a second pivoted latch element carried by the casing and engageable with a latch element on the oscillatable member to hold it in and release it from a tensioned position, said second latch including a cam arm, a shutter lever engaging said cam arm and adapted to be manually actuated in one direction to move said arm and release the oscillatable member, said shutter lever being movable in an opposite direction to set said mechanism for an exposure, a spring latch on said second latch and movable therewith to and from a shutter lever engaging position, an arm on the shutter lever for setting the oscillatable lever, means carried by the shutter lever for engaging the spring latch towards the end of its setting movement preventing movement in a reverse direction until said setting lever is fully moved to set the mechanism, and means carried by the oscillatable member for releasing the spring latch.

38. The camera shutter as defined in claim 37 characterized by said oscillatable member including a tooth for moving the spring latch out of engagement with the shutter lever when the oscillatable member reaches a set position.

39. The camera shutter as defined in claim 37 characterized by a shutter lever for simultaneously setting both the master member and the oscillatable lever, said spring latch preventing the operation of the shutter unless'both the master member and the oscillatable lever are fully set.

40. In a camera of the type including an apertured casing, two interconnected blade rings movably mounted in the casing, shutter blades operatively connected to the blade rings for movement to make an exposure through the shutter casing aperture, the combination with said blade rings, of a master member, means for setting and releasing the master member, said means including an operating lever, an oscillatable member, a latch normally engaging the oscillatable member and lying in the path of movement of the operating lever, a spring latch on said latch normally engaging the oscillatable member movable into and out of an operatin lever engaging position, means included in the operating lever moving towards a setting position to engage said spring latch towards the end of its setting movement for holding the operating lever against movement in a releasing direction until the shutter is fully set, and means carried by the oscillatable member for releasing said spring latch when the shutter is fully set, said operating lever including an arm for setting the oscillatable member when said operating member is moved to set the master member.

ii. A shutter as defined in claim 40 characterized by the latch normally engagin the oscillatable member being spring operated into engagement therewith, and the spring latch carried thereby including a downwardly projecting flange adapted to be moved transversely of an upwardly extending flange on the operating lever when said oscillatable lever is moved by the operating lever.

42. In a camera of the type including an apertured casing, two interconnected blade rings 

